Home & Calculator


Modified Duke Criteria for Infective Endocarditis

Pathologic Criteria
Microorganisms demonstrated by culture or histologic examination of a vegetation,a vegetation that has embolized, or an intracardiac abscess specimen; or

Pathologic Lesions: Vegetation or intracardiac abscess confirmed by histologic examination showing active endocarditis

Major Clinical Criteria
Blood culture positive for IE
  • Typical microorganism consistent with IE from 2 separate blood cultures
    • (Viridans streptococci, Streptococcus bovis, HACEK group, Staphylococcus aureus; or Community-acquired enterococci, in the absence of a primary focus); OR
  • Microorganisms consistent with IE from persistently positive blood cultures, defined as:
    • At least 2 positive cultures of blood samples drawn >12 hour apart; or
    • All of 3 or a majority of >= 4 separate cultures of blood (with first and last sample drawn at least 1 hour apart)
  • Single positive blood culture for Coxiella burnetii or antiphase I IgG antibody titer >1:800

Evidence of endocardial involvement

1 TEE, transoesophageal echocardiography; TTE, transthoracic echocardiography.
Minor Clinical Criteria2
2 Echocardiographic minor criteria eliminated
Predisposing heart condition or injection drug use

Fever, temperature > 38°C (or 100.4°F)

Vascular phenomena: major arterial emboli, septic pulmonary infarcts, mycotic aneurysm, intracranial hemorrhage, conjunctival hemorrhages, and Janeway’s lesions

Immunologic phenomena: glomerulonephritis, Osler's nodes, Roth’s spots, and rheumatoid factor

Microbiological evidence: positive blood culture but does not meet a major criterion as noted above3 or serological evidence of active infection with organism consistent with IE

3 Excludes single positive cultures for coagulase-negative staphylococci and organisms that do not cause endocarditis.
Rejecting criteria
Firm alternative diagnosis explaining evidence of IE.

Resolution of IE symptoms with antibiotics for ≤ 4 days.

No pathological evidence of IE at surgery or autopsy, with antibiotic therapy ≤ 4 days


infective endocarditis according to Modified Duke Criteria.



“Definite” IE:

  • One or more pathologic criteria, or
  • Clinical criteria
    • 2 major criteria, or
    • 1 major and 3 minor criteria, or
    • 5 minor criteria

“Possible” IE:

  • 1 major criterion and 1 minor criterion, or
  • 3 minor criterion


  • Firm alternative diagnosis explaining evidence of IE, or
  • Resolution of IE symptoms with antibiotics for <= 4 days, or
  • No pathological evidence of IE at surgery or autopsy, with antibiotic therapy <= 4 days, or
  • Does not meet criteria of “possible” IE, as above.